Method for activating compositions of carbon, hydrogen, and sulfur



Oct. 10, 1950 lB. w. GAMsoN v METHOD FOR ACTIVATING COMPOSITIONS 0F' CARBON, HYDROGEN, AND SULFUR Filed June 16, 1948 amv wir'

Patented Oct. 10, 1950 METHOD'FOR GTIVATING COMPOSITIONS S011"4 CARBON;HYDROGEN,V AN D.. SULFUR ."BernardWfGamson, Mortonv Grove, lll., assigner ".to iGreat'Lakes"'.Carbon Corporation, Morton This invention relatesl to.. a` method 1 for. activating compositions composed of carbon, vhydrogen and sulfur by treatment Withsulfur vvapor at temperatures between about:1100-1800F.

may be present, depending on the compositionfof the organic raw material used.

These. compositions are referred .to as sulfo-hydrocarbons. Usually,V advantage istakenof .the

The sulfur-carbon-'hydrogen compositions with 5 liquid condition of the mixture initially formed, which this invention is concernedY are prepared before conversion to a solid statewithintne range by reacting elemental sulfurwithA hydrocarbonaof 45o-625 EL, t@ pyoduce-the-so1id-n ,thaform ceous or heavyhydrocarbon` materials underco-nn of discrete particles of desired size. This can-be ditions to produce a hard, infusible, dense;v amordone by spraying the. liquid ontoheatedparticles phOllS Substance. The methOClOf. fOlmIlgnthS 10 0f the Sulf0hydr0ga1lb0n formed in a, prior ppis the subject of .my co-pending application eration under such conditionsthat the sulfo-hy- 649,730, led February 23, 1946, now Patent No. drocarbon builds up to form balls. :According-to 2,447,004, issued August 17, 1948. another method, a fnesprayof the liquid maybe In general. the basic raw material is.- prepared injected into a heated zoneunder conditions such by forming'a uniform liquid mixture ora high- 15 that individual droplets will be converted-.into boiling hydrocarbon followed by. heatingzattemsolid particles of the desired dimension. v.Minute peratures of about-4004800? F. toproduce the solid particles or dust of the sulfofhydrocarbon solid substance. VHydrocarbons*suitable in the may be kept in a iiuidized statein the reaction process are those liquid OrliqUeabIe within the Zone and permitted togrow in particle sizeY .by range of about SOO-450 F. and-.havinga hydrogen 20 deposition of the liquid mixtureY sprayed on the content of about .4 to 4about 12%. Hydrocarfine suspended solids followed by its hardening bonaceous substances such as coal which.: are as the reaction proceeds. solid in the above-noted :temperature rangedo The sulfo-hydrocarbon thus prepared' is then not produce the active products of the present heated in a separate step to atemperature in invention. 25 the range of about 1100-1800 F4 generally in an The amount of sulfuremployed inmakingthe inert atmosphere. Hydrogen sulfide .is evolved base material for subsequenta'ctivationushould due to the pyrolysis of the sulfo-hydrocarbon. be at least 60% of the stoichiom'etric:equivalent The lresulting product is black in -color,nhard, of the hydrogen content-of thehydrocarbonfmadense, insoluble, infusible and inactiveinsofar terial to be reacted with it. .Preferably90-,1l0% 3o as the usual gas absorption, decolorization, etc., of sulfur is employed. l A uniformmiXtureis-made operations are concerned. TheY substance hasthe by mechanicallymixing elemental sulfur, usually composition in the range asfollowsl and, is vrein finely divided form, with the hydrocarbon. ferred to asasulfocarbon.

This may be done"'using"a hot mixture, or the mixture maybe first made and then. heated. It 3.3 l'fj tgtgggut 0 3,7 is highly important` that.l agitation and'pheating Su1fm :'2 2`5% .to aboutq m0 be continued until a uniform liquid'fmixture nis Ash, OZB-hun," v 01%50 about 21.5% obtained. Ordinarily, :temperaturesaround 350 Real density 1 5mvabout 1 '9' F. are suitable and the general'rangeof 30D-450 i. ,Y F. maybe employed. Thetemperature'is then -40 hve pevlqusly dfsclosed m my Copenfil-ng increased to a point` within ntheran-ge `ofrabout Damen lpp 1.0951011 Teieled to above that the 45048000 R This may be. donedntwo Steps, sili tocar on Jutst described 1s substantially comrst increasing the temperature Vto--about-500- p-e ely Comer me to carbon dlsumde by leacv tion with sulfur vapors at a temperature` between 625 F. until the mixture ofv hydrocaibonnand o.

, Y about 1100-1800 E I have further discovered Y. h I however, that 1f this reaction is stopped after 13h15 pOlIlt a hard, lnfuslbie, 11150191319, anofphous about 10% to about 90% of the sulfocarbon'` has substanceis formed having the followlng range been Consumed that the..so1d. residuehas. the of compositions. f properties of a highly activatedcarbon and is Carbon About 47%.t0 aboutz70z% 50 suitable for use, without further treatment, as Hydrogen `Abcut 4.0%.,0 about 13% an activated carbon. The `activated Lmaterial Sulfur From about 5o% vtoamut,25% thus produced preferablyj comprises from about Real density From about 1.3% to about 13% 65% t0 about 90% 0f the Original'slllforCalbOrl.

The sulfohydrocarbon and sulfocarbon arevery Up to about .2l/2% of oxygen, nitrogen and ash ,55 hard and dense materials. 'For'manypurposes these are too hard to grind to the requisite degree of neness in an economical manner prior to activation. By the present activation treatment, however, the resulting products are rendered lessv dense and more friable, thus can be readily ground to ne powders; e. g., through 200 or 300 mesh screen for use in water purification, or as an active filler for rubber.

Under certain conditions it may be advisable to further treat the sulfur-activated residue for a short period of time in an oxidizing atmosphere of steam or carbon dioxide. This reduces the combined sulfur content f the residue and for certain purposes improves its activity.

The activated carbonaceo-us body thus produced may be used to decolorize mineral and vegetable oils, sugar solutions, and various chemical solutions for which the recognized activated carbons of commerce are usually employed. activated material thus produced may also be employed as a filler for Various purposes, especially where an activated particle surface is desired. It can be included as a reinforcing agent in the compounding of natural or synthetic rubber. This may be done by grinding or otherwise comminuting the residue to a particle size of the order of 100 millimicrons. To facilitate the production of my activated carbonaceous solids, the sulfo-hydrocarbon may be produced in the form of fine particles by injecting the liquid charge mixture of hydrocarbon and sulfur into a hot zone in the form of a fine mist to be converted thereto a solid powder. Upon calcining this powder at a temperature of l200-l800 F. and then treating it with sulfur vapor at a temperature of about 1l00-1800 F. and preferably at about 1200-1600 F., a part of the carbon in this sulfocarbon powder is consumed. This has the effect not only of activating the material but of further reducing the particle size and apparently of rendering it particularly susceptible of pulverization to the extent required for use in the compounding of rubber and the like.

The activated carbonaceous products of the present invention may be produced in varying f degrees of density and therefore have advantages especially applicable to various requirements. A relatively dense, strong carbon for gas :absorption can be made by an activation-consumption of 40% of the carbon content of the Icarbonaceous solids charged. A less dense material for other purposes such as decolorization of oil, sugar, chemicals, etc., can be made by more prolonged activation. The absorption activities compare well with the best activated carbons known in commerce.

In the activation process it is preferred to react thecarbonaceous material with sulfur vapor at such a temperature as will give a maximum yield of product for a given activity. It has been found that this requires that the material be calcined at a temperature slightly below, say 50 C., than that at which it is to be activated.

Referring now to the gures which appear in the appended drawings, further correlaticn of activation conditions will be made clear.

Figure 1 shows the general relationship between activity and the density of the activated material. The activity is expressed as heat of wetting in m-xylene as calories per cubic centimeter of the activated material tested by the method described in Ind. Eng. Chem., vol 34, pp. 14 and 131, (1942). The density is expressed as the bulk density of the granular sample which has been gravity packed by gentle tapping in a The 4 laboratory graduate of suitable size. The correlation shown in this figure has been found to be substantially independent of the temperature of activation in the useful range of about 1200-1800 F.

Figure 2 shows the general relationship I have found to exist between the bulk density of the activated material and the weight'percentage of the original material remaining after activation with sulfur vapor. The eifect of the temperature of activation upon the bulk density of the activated material is shown in this gure by the curves obtained at the various temperatures from 1400 to 1800 F. It will be noted here that to ,obtain a given bulk density, with least consumption of the original material, the higher temperatures. ofactivation are to be preferred. For example, at 1800 F. a yyield of 63% of the charge is obtained, .while at 1400 F. the yield is about 50%, both products having the bulk density of 0.6 gm./cc., and the same activity.

Figure 3 shows therelationship between the bulk density-and the temperature of activation, which relationship is also affected by the degree of consumption to be desired during activation. Curves are shown for various percentage yields ofV activated products obtained. From this figure it can be seen, for example, that at 50% yield of activated product, products having various densities each suited to'specific uses may be obtained depending on the temperature of activation employed.

The bulk density `factor which appears in the foregoing correlations is a measure of the internal porosity of the granules of the activated product. It is the control of such porosity which is a determining factor in the application of the activated product for specific adsorptive purposes. The conditions for development of various degrees of porosity in activation have been described in connection with the various correlations brought out in Figures 1 3. It should be kept in mind that whatever temperature is selected for the activation treatment, the sulfocarbon charge material should not be calcined above that temperature, but preferably slightly below it as already indicated. The material is less reactive with sulfur vapor if calcined at a temperature above the activation temperature.

The following example illustrates the utility of the process but should not be construed as limiting it to the exactrconditions employed.

Example An activated carbon was prepared as follows:

A heavy cracked petroleum residue, liquid at room temperatureV F.) was mixed with the stoichicmetric equivalent of sulfur (based on hydrogen content of 8%). The mixture was heated to 350 F. until uniform, and then heated at 500 F. until it became hard and infusible. It was broken up to pass a 4 mesh screen and heated in a tube to 1400o F. Sulfur vapor was passed over it at 1420o F. until 76.8% of the carbon was consumed by conversion to carbon disulfide, a valuable byproduct. The residue contained 68.5% carbon, 0.3% hydrogen and 23.6% sulfur. The

sulfocarbon before activation contained 75.9%

under various conditions and the data in the appended curves were obtained.

I claim as my invention:

1. A process for manufacturing activated carbonaceous compounds which comprises reacting a sulfocarbon With sulfur vapors at a. temperature of about 1100-1800 F. to consume approximately -90% of the sulfocarbon.

2. A process for manufacturing activated carbonaceous compounds which comprises reacting a sulfocarbon with sulfur vapors at a. temperature of about 12.00 to about 1600 F. to consume approximately 10-65% ofthe sulfocarbon and recovering the unreacted carbonaceous substance.

3. A process which comprises reacting a sulfocarbon with sulfur vapor at a temperature of about 1100-1600 F. until about 10-65% has disappeared, separating the residue and contacting it with an oxidizing agent selected from the group consisting of steam and carbon dioxide.

4. A process for producing an activated carbonaceous substance which comprises heating a sulfo-hydrocarbon at a temperature in the range of about 1100-1800 F. thereafter contacting the thus heated body with sulfur vapor at a temperature of about 1100-1800 F. thereby consuming at least 10% of the sulfocarbon, and recovering the activated material.

5. A process which comprises forming a, uniform mixture of a hydrocarbonaceous substance having a hydrogen content of about 4% to about 12% and being liquid in the range of about 300- 450 F. with elemental sulfur in proportions of about of the stoichiometric equivalent of the hydrogen content of said substance, converting the mixture to an infusible solid at 450- 625` F., thereby further dehydrogenating it by evolving hydrogen in the form of hydrogen sulde, thereby producing a dense, hard, infusible, insoluble, amorphous substance having a density of about 1.5 to about 1.9, a carbon content of about rI0-93%, a hydrogen content of about 0.3 to about 1.8%, and sulfur content of about 6% t0 about 25% said sulfur being combined chemically with said hydrogen and carbon, thereafter contacting the material with sulfur vapor at a temperature in the range of about 1100-1800 F.,

continuing said contact until about 10-90% of REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Name Date Gamson Aug. 17, 1948 Number 

1. A PROCESS FOR MANUFACTURING ACTIVATED CARBONACEOUS COMPOUNDS WHICH COMPRISES REACTING A SULFOCARBON WITH SULFUR VAPORS AT A TEMPERATURE OF ABOUT 1100-1800*F. TO CONSUME APPROXIMATELY 10-90% OF THE SULFOCARBON. 